| 1 | #!/bin/sh
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| 2 |
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| 3 | # The previous if-conditionals were string comparisons. We will now take
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| 4 | # a look into using number comparisons.
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| 5 | #
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| 6 | # -eq # equal to
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| 7 | # -ne # not equal to
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| 8 | # -gt # greater than
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| 9 | # -ge # greater than or equal to
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| 10 | # -lt # less than
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| 11 | # -le # less than or equal to
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| 12 | #
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| 13 | # Also, when you input a number from the 'read' command, it
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| 14 | # automatically becomes a integer. Shell cannot use float or doubles.
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| 15 | # To use decimal numbers, you must delegate it to other tools that will
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| 16 | # be taught much later
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| 17 | #
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| 18 | # $ read user_input
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| 19 | # $ if [ $1 -eq 1412 ]; then
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| 20 | # $ echo "Correct pin"
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| 21 | # $ fi
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| 22 | #
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| 23 | # You can also do operations but these must be surrounded by double
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| 24 | # parenthesis.
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| 25 | #
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| 26 | # $ $((10 + 2)) # 12 addition
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| 27 | # $ $((10 - 2)) # 8 subtraction
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| 28 | # $ $((10 * 2)) # 20 multiplication
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| 29 | # $ $((10 / 2)) # 5 division
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| 30 | # $ $((-10 % 3)) # -1 modulo, finds out the remainder
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| 31 | #
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| 32 | # Write a script that tells you if an inputted number is even or odd.
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| 33 |
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| 34 | num=$1
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| 35 |
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| 36 | echo "odd"
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| 37 | echo "even"
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